Synthetic resin



Patented June 21, 1938 I UNITED STATES SYNTHETIC RESIN Israel Rosenblum,Jackson Heights, N. I.

No Drawing. Application November 3, 1934,

Serial No. 751,419

1'! Claims.

The present invention relates to the production of synthetic resins ofthe phenol-formaldehyde type and has for its object 'to produce anoilsoluble resin by the reaction of a phenolic body 5 and an aldehyde,preferably formaldehyde either in aqueous solution or in the form of apolymer; such resins having a high molecular weight and beingcharacterized by substantially complete non-reactivity and possessing,even when not treated with an esterifying or neutralizing agent,

a relatively low acid number.

The present application is a continuation-inpart of my copendingapplications Ser. No. 594,379, filed Feb. 20, 1932; Ser. No. 580,495,filed Dec. 11, 1931; and Ser. No. 538,248, filed May 18,

1931. It is an object of the present invention to produce a resin of thetype indicated above which is more or less permanently fusible, that is,can be repeatedly melted for an indefinite period of time and brought tothe liquid condition without becoming permanently hardened, that is,rendered infusible. The resins of my improved type are thus stable atthe temperatures commonly employed in the art of varnish making, andwill not cresol) to about 2 mols of formaldehyde per mol.

of phenol in the case of more or less pure para cresol, and even higherproportions of formalde-. hyde in the case of mixtures of ordinaryphenol (carbollc acid) and the higher phenol homologues, such as paratertiary butyl and amyl phenols and in the case also of such higherhomologues in the absence of ordinary phenol.

It is a particular object of the present invention to provide a simpleand inexpensive process for obtaining fusible and oil-solublephenolaldehyde resins wherein the phenolic body comprises a mixture ofordinary phenol and the higher homologues of phenol, such homologueshaving substituting groups preferably in the para position, oil-solubleresins being obtained even though the proportion of ordinary phenolpreponderates considerably over that of the higher homologue orhomologues.

I have found that phenol-aldehyde resins of an improved character can beobtained by effecting the condensation of the phenolic and aldehydebodies in the presence of a high boiling terpene hydrocarbon, such asdipentene. By high boiling terpene hydrocarbons I mean those which boilabove pinene, which is the primary component of turpentine. If desired,the dipentene or equivalent high boiling hydrocarbon may be added to!the reaction mixture after the condensation has proceeded to someextent.

In accordance with the invention, the phenol or mixture of phenols andthe aldehyde are condensed in the presence, for example, of dipenteneand preferably also in the presence of a catalyst at a, temperature ofabout C. under reflux or at about C. under pressure. The water ofsolution of the formaldehyde is then expelled, after which thetemperature is slowly raised to approximately the boiling point of theterpene hydrocarbon to expel volatile matter. The temperature may thenbe raised until a resin of the desired hardness is obtained. In thisway,I obtain an oil-soluble resin which is solid at room temperaturesand is characterized by high molecular weight, a commercially low acidnumber-and more or less permanent fusibility. My improved resins arenon-reactive in character, by which I mean that the exothermic reactionresulting in the formation of the resinous condensate is substantiallycompleted and the resin will ordinarily not foam and become appreciablyharder or infusible on heating. The resins are thus practically nolonger self-reacting, that is, they are not potentially reactive,although they may, of course, and can react with other bodies,

such as varnish oils, neutralizing agents, etc. I

This property of non-self-reactivity I have observed in a. large numberof resins produced by me in accordance with the present invention, butit is to be understood that although I prefer to carry the condensationto the point where a resin solid at room temperature and no longerself-reactive is obtained, the invention is not limited to theproduction of a solid or of a nonreactive or stable material, as thereaction may be stopped at a point at which the resin is capable offurther reaction and condensation.

The resins produced in accordance with the present invention arecompatible with the usual solvents for such resins and also with naturalresins and their esters and can be mixed inv all proportions therewith.If desired, a natural resin or its ester may be present during thecondensation of the phenol and formaldehyde, and when an acidic naturalresin is employed, it maybe neutralized in known manner. The resins formstable solutions in or reactionv products with varnish oils and yieldlustrous hard flexible strongly adhering fllms when made up intovarnishes, paints and enamels or other coating compositions.

I have found'that heating of the reaction mass to the boiling point ofthe dipentene or equivalent high boiling hydrocarbon and even to highertemperatures does not operate to expel all of the dipentene. Ittherefore appears that, in spite of the fact that hydrocarbons areordinarily characterized by inertness, the dipentene has entered intosome kind of chemical reaction or changed the usual course ofcondensation, producing compounds whichfare characterized byoil-solubility, stability and fusibility and low acid value.

The reaction may and preferably does take place in the presence of acatalyst, which among other things effects rapid binding of the terpenematerial and of the aldehyde and thus prevents loss of valuble material.While the known acid "and basic catalysts may be employed, I prefer touse the more or less neutral organic salts of zinc, calcium, barium,strontium, lead, cobalt, manganese, nickel, etc. The use of zinc acetateor abietate is preferred. The oxides of the metals can also be used.

The invention will be further described in greater detail by referenceto the following examples which illustrate several modes of carrying outthe same.

Example 1 108 grams (1 mol.) cresol-(commercial mixture of ortho, meta,and para cresol) 60 grams (0.8 mol.) 40% formaldehyde solution 108 gramsdipentene 10 cc. 2N hydrochloric acid are condensed in a flask byheating'at the boiling point with a reflux condenser forabout fourhours. The material is then dehydrated by removing the condenser andheating to C. The dipentene which is carried over with the expelledvapors is returned to the flask or is replenished. The heating is thencarried to higher temperatures (about 220-250 C.)-' to effect a furthercondensation reaction, until a resin which is solid and brittle at roomtemperature isobtained, dipentene being expelled during such heating.This resin containing only about 10% combined dipentene is permanentlyfusible and is soluble in fatty oils.

When the same condensation is carried on with out the dipentene, a resinis obtained which, although fusible, is not soluble infatty oils.

Example 2 108' grams (1 mol.) cresol (ortho, rneta, para) 60 grams (0.8mol.)- 40% formaldehyde solution 108 grams dipentene v the same mannerwithout'dipentene, a plastic resin is obtained already after two hoursheating at C. By careful heating at C. (as the resin is reactive) abrittle resin is obtained. At no stage is this resin soluble in fattyoils.

Example 3 108 grams (1 mol.) para cresol 150 grams (2 mols) 40%formaldehyde solution 10 cc. 2N hydrochloric acid 108 grams dipenteneare condensed by refluxing at boiling point for about four hours. Thecondenser is then removed and the material is dehydrated and the carriedover dipentene replenished. The heating is now 1 carried on to highertemperature to remove vola-- tiles, including most of the dipentene, thecon- Example 4 108 grams (1 mol.) par'a cresol 150 grams (2 mols) 40%formaldehyde solution 108 grams dipentene 0 25 gram zinc acetate ascatalyst are condensed by refluxing at the boiling point for about 15hours. The condenser is then removed and the material dehydrated andthen heated to about 130 C. at whichtemperature it is kept for two hoursfor further condensation. The dipentene which is carried over with thedistilled vapors is replenished and the heating is then carried on athigher temperatures. At C. a resin is obtained which is solid andbrittle at room temperatures. The resin contains about 15% combineddipentene and is soluble in fatty oils on moderate heating.

Without dipentene an oil-insoluble resin is obtained under the sameconditions.

Example 5 '71 grams mol.) phenol 41 grams (A mol.) amyl phenol 225 grams(3 mols) 40% formaldehyde 0.25 gram zinc acetate grams dipentene arecondensed by refluxing at the boiling point for about 15 hours. Thematerial is dehydrated, then heated to about 130 C. and kept at thistemperature for about 2 hours. Care should be taken to replenish thedipentene lost with the distilled vapors so that the amount of dipentenepresent should again about equal the weight of phenols.

The material is now heated to a higher temperature to remove volatilematter, until at about 200 a resin is obtained which is solid andbrittle at room temperature, the resin containing about 15% of combineddipentene. It is readily soluble in fatty oils.

When the same operation is carried out without dipentene, a resin isobtained which is already hard after the heating to about 150 C. and isnot soluble in fatty oils at any stage.

Example 6 7 Same as in Example except that instead of amyl phenol, butylphenol is used. In both examples the use of the paratertiary phenol ispreferred. 1

Example 7 164 grams (1 mol.) amyl phenol 225 grams (3 mols) 40%formaldehyde solution 164 grams dipentene 1 gram zinc acetate arecondensed by refluxing for about 15 hours. The condenser is then removedand the material is dehydrated, the temperature is then brought up toabout C. and kept there for about 2 hours. It is then heated to about250 until practically all volatile matter is removed. A pale brittleresin of acid number about 35 is obtained, which is soluble in fattyoils on moderate heating.

Without dipentene a dark, non-stable. selfreactive resin is obtained ofacid number about 90.

Example 8 Any of the previous Examples 1-7 is carried out in presence ofany desired proportion of natural resin ester, such as glyceroltriabietate.

Example 9 Any of the previous Examples 1-7 is carried out in thepresence of any desired proportion of rosin. At about C. about 10%glycerol (based on the weight of rosin) is added and the esterificationcarried out in known manner.

In all of the above examples, the initial condensation may take placeunder pressure (about 10 lbs.) at about 110 C. in place of under reflux.

While I prefer to carry the condensation to the point at which a resinsolid at room temperature is obtained, the reaction may be stopped at anearlier stage as indicated above, or various materials, such as solventsor varnish oils, may be added so that a coating composition or oilvarnish is obtained as the final product.

The proportions of materials, temperatures,

times of heating etc. may be varied from those specified hereinabove,especially when batches of different sizes are worked with, withoutdeparting from the spirit or scope of the invention.

I claim:

1. The method which comprises reacting a phenolic body including ahomologue of phenol, with an aldehyde 'in the presence of a terpenematerial consisting primarily of dipentene until a resin containing aconsiderable proportion of dipentene in chemical combination isobtained.

2. The method which comprises reacting a mixture of phenols withformaldehyde in the presence of a terpene material consisting primarilyof dipentene and continuing the condensation at approximately theboiling point of the mixture until an oil-soluble resin which is solidat room temperature and containing a'considerable proportion ofdipentene in chemical combination is obtained.

3. The method which comprises reacting a major proportion of phenol anda minor proportion of a para-alkyl phenolwith formaldehyde in thepresence of a terpene material consisting primarily of dipentene and ofa catalyst until an oil-soluble resinous reaction mass containing aconsiderable proportion of dipentene in chemical combination isobtained.

4. The method which comprises reacting a mixture of phenol and amylphenol with formaldehyde in the presence of a terpene materialconsisting primarily of dipentene and of a catalyst, expelling the waterand then heating the reaction mass to approximately the boiling point ofthe dipentene and continuing the heating until uncombined dipentene hasbeen expelled and an oil-soluble resin which is solid at roomtemperature and contains a considerable proportion of dipentene inchemical combination is obtained.

5. Thelmethod which comprises reacting an initial condensation productof a phenolic body including a homologue of phenol, and an aldehyde witha terpene material consisting primarily of dipentene, continuing thereaction at approximately the boiling point'of the mixture until most ofthe dipentene has been expelled and an oil-soluble resin which is solidat room temperature and contains at least about 10% of dipentene inchemical combination is obtained.

6. An oil-soluble resin substantially solid at room temperature andcomprising the reaction product of the condensate of approximately 1mol. of para cresol and 2 mols of formaldehyde, and a terpene materialconsisting primarily of dipentene, said resin containing a considerableproportion of dipentene in chemical combina-' tion.

'7. An oil-soluble, substantially solid and nonreactive resin comprisingthe reaction product of a condensate of approximately 1 mol. of amylphenol and 3 mols of formaldehyde, and a terpene material consistingprimarily of dipentene, said resin containing a considerable proportionof dipentene inchemical combination.

8. The method of improving the oil-solubility of phenol-formaldehyderesins which comprises reacting a mixture containing a substantialproportion of phenol and at least one of the group of phenol homologuesconsisting of butyl and amyl phenols with formaldehyde in the presenceof a terpene material consisting primarily of dipentene until an initialcondensate is produced, and then heating the mass to temperatures of theorder of 200-250 until substantially all of the volatile matter has beenexpelled.

9. The method which comprises effecting chemical combination between aphenolic body, a terpene material consisting primarily of dipentene andan aldehyde in the presence of a catalyst until a fusible, soluble resincontaining a considerable proportion of dipentene in chemicalcombination is obtained.

10. The method which comprises eflecting chemical combination between aphenolic body, a terpene material consisting primarily of dipentene, andformaldehyde with the aid of hydrochloric acid until a fusible andsoluble resin containing a considerable proportion of dipentene inchemical combination is obtained.

11. The method which comprises effecting chemical combination between aquantity of a phenolic body, an approximately equal quantity ofdipentene, and an aldehyde in the presence of a catalyst.

12. A resinous condensate suitable for the manufacture of coatingcompositions and containing in chemical combination a phenolic body, analdehyde and a terpene material consisting primarily of dipentene.

13. A fusible and soluble resin containing in chemical combination aphenolic body including a homologue of phenol, an aldehyde and a terpenematerial consisting primarily of dipentene.

14. An oil-soluble resin solid at room temtion a mixture of phenol and ahomologue of phenol. formaldehyde and a terpene material consistingprimarily of dipentene.

15. An oil-soluble resin substantially solid at room temperature andcomprising the reaction product of approximately 1 mol. of. mixedcresols,

0.8 moi. of formaldehyde, and a terpene material consisting primarily ofdipentene, said resin containing a considerable proportion of dipentenein chemical combination.

16. A fusible, resinous condensate, solid at room temperature andsuitable for the manufac- 'perature and containing in chemicalcombinaprimarily of dipentene, and produced with the 10 aid ofhydrochloric acid.

ISRAEL ROSENBLUM.

